ParsedCiphertext throws an error if it is not complete

src/main/java/com/amazonaws/encryptionsdk/ParsedCiphertext.java

@@ -1,11 +1,11 @@
 /*
  * Copyright 2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
- * 
+ *
  * Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file except
  * in compliance with the License. A copy of the License is located at
- * 
+ *
  * http://aws.amazon.com/apache2.0
- * 
+ *
  * or in the "license" file accompanying this file. This file is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
  * specific language governing permissions and limitations under the License.
@@ -15,6 +15,8 @@
 
 import com.amazonaws.encryptionsdk.internal.Utils;
 import com.amazonaws.encryptionsdk.model.CiphertextHeaders;
+import com.amazonaws.encryptionsdk.exception.BadCiphertextException;
+import com.amazonaws.encryptionsdk.exception.ParseException;
 
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 
@@ -33,9 +35,12 @@ public class ParsedCiphertext extends CiphertextHeaders {
      * {@code ciphertext} and that any changes made to the backing array will be reflected here as
      * well.
      */
-    public ParsedCiphertext(final byte[] ciphertext) {
+    public ParsedCiphertext(final byte[] ciphertext) throws ParseException {
         ciphertext_ = Utils.assertNonNull(ciphertext, "ciphertext");
         offset_ = deserialize(ciphertext_, 0);
+        if (!this.isComplete()) {
+          throw new BadCiphertextException("Incomplete ciphertext.");
+        }
     }
 
     /**

src/test/java/com/amazonaws/encryptionsdk/model/CiphertextHeadersTest.java

@@ -1,11 +1,11 @@
 /*
  * Copyright 2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
- * 
+ *
  * Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file except
  * in compliance with the License. A copy of the License is located at
- * 
+ *
  * http://aws.amazon.com/apache2.0
- * 
+ *
  * or in the "license" file accompanying this file. This file is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
  * specific language governing permissions and limitations under the License.
@@ -161,10 +161,10 @@ public void serializeWithNullHeaderTag() {
      * dataKey_ = new AWSKMSDataKey(testKey_, encryptedKey_);
      * headerNonce_ = ByteFormatCheckValues.getNonce();
      * headerTag_ = ByteFormatCheckValues.getTag();
-     * 
+     *
      * Map<String, String> encryptionContext = new HashMap<String, String>(1);
      * encryptionContext.put("ENC", "CiphertextHeader format check test");
-     * 
+     *
      * final CiphertextHeaders ciphertextHeaders =
      * createCiphertextHeaders(encryptionContext);
      * //NOTE: this test will fail because of the line below.
@@ -173,7 +173,7 @@ public void serializeWithNullHeaderTag() {
      * messageId_ = ciphertextHeaders.getMessageId();
      * final byte[] ciphertextHeaderHash =
      * TestIOUtils.getSha256Hash(ciphertextHeaders.toByteArray());
-     * 
+     *
      * assertArrayEquals(ByteFormatCheckValues.getCiphertextHeaderHash(),
      * ciphertextHeaderHash);
      * }
@@ -314,6 +314,24 @@ private void readUptoNonceLen(final ByteBuffer headerBuff) {
         headerBuff.get();
     }
 
+    @Test(expected = BadCiphertextException.class)
+    public void incompleteCiphertext() {
+        final Map<String, String> encryptionContext = new HashMap<String, String>(1);
+        encryptionContext.put("ENC", "CiphertextHeader Streaming Test");
+
+        final CiphertextHeaders ciphertextHeaders = createCiphertextHeaders(encryptionContext);
+        final byte[] headerBytes = ciphertextHeaders.toByteArray();
+        final ByteBuffer headerBuff = ByteBuffer.wrap(headerBytes);
+
+        readUptoVersion(headerBuff);
+
+        // set ciphertext to incomplete.
+        headerBuff.put((byte) 0);
+
+        final CiphertextHeaders reconstructedHeaders = new CiphertextHeaders();
+        reconstructedHeaders.deserialize(headerBuff.array(), 0);
+    }
+
     @Test(expected = BadCiphertextException.class)
     public void invalidType() {
         final Map<String, String> encryptionContext = new HashMap<String, String>(1);